Vehicle jack



Sept. 30, 1941.

w. BEHM E-rAL VEHICLE JACK Filed Sept. 16, 1940 2 Sheets-Sheet 1 maentors Walhzr Bzhm, Earl J. Hc ClllimJr.

Sept. 30, 1941. w, BEHM ETAL 2,257,324

VEHICLE JACK Filed Sept. 16, 1940 2 Sheets-Sheet 2 mnentors Valier Behr, Ear] :I McClellanJr y Ctttomega Patented 3o, 1941 'UNITED' STATES PATENT oFF-rcs I Vr i #man september 1s, im, sew Noi 356.914

nous.

This invention relates to vehicle lacks and particularly jacks suited for permanent installation on vehicles. r

In equipping vehicles with jacks and permanently installing the latter in positions of use, the problem arises of locating the-jacks at a height adequate for proper normal ground clearance despite limitations imposed by the body and other parts of the vehicle. One of the iactors tending to increase requisite vertical liift` frame. and to adapt the jack. when being extended, to exercise an axle-supporting function,

so as to avoid material sagging of the axle and load-transmitting springs, thus minimizing requisite vertical lift.

.Another object is to form a jack iorv aforesaid purpose oi telescoping sections, normally housed one within another in a raised position, and adapted to be lowered responsive to applied fluid pressure, and to 'avoid imposing effective iiuid pressure on the ground-engaging section of the jack until a mid section has fully responded to such pressure, travel of such mid section being utilized to render a support eilective on an axle adjacent to the jack.

These and various other objects the invention attains by the construction hereinafter described and illustrated in the accompanying drawings. wherein:

Fig. l is a vertical sectional view of the extended and loaded jack.

Fig. 2 is a similar view of the jack as retracted to its normal position of non-use.

Fig. 3 is a fragmentary horizontal sectional view oi the jack, particularly showing the pivoting on the upper jack section of an axle-supporting arm.

Figui is an elevational view of the raised or collapsed jack, as viewed transversely to the adjacent axle.

Fig. 5 is a view similar to Fig. 1 but showing -a modiiled construction.

Fig. 6 is a top plan view oi the modincation.

(Cl. 25d-88) notes the cylindrical upper section of a telescoping sectional jack, said section having its upper end closed by a detachable head 2 through which a hose .or pipe l opens for delivering compressed 5 air or someother pressure iluid. u

Slidingly engaged within the section I and projecting variably below such section is a cylindrical mid section I closed at its upper end by a detachable head i slightly exceeding the section l in diameter. A cup leather i secured upon the headibyametal diskl andbolttismarginally upturned for sealing contact with the section I and an air passage through said head is normally closed'by a check valve downwardly seated by a coiled spring. I0.

Slidably engaged in and variably projecting below the section 4 is a bottom cylindrical section I I permanently closed at its upper end by a head I2 oi slightly greater diameter than the section I I and carrying a cup leather I3 marginally upturned for sealing engagement with said section. the lower end oi s'aid bottom section being equipped with a suitable base Il for the jack.

Within the lower portions of the sections I and `I, packing I5 is compressed around the inserted sections, by annular gland nuts I6, such packing being upwardly seated against annular ribs I1 rigidly interiorly carried by said sections I and l. These ribs further form abutments 'for the tween the ribs and heads i and I2 and tending thus to normally raise the sections 4 and Il to position shown in Fig. '2, disposing them both within the section I.

When the mid section of the jack is in its lowermost position (Fig. l) it uncovers the upper end ci a huid by-pass Il formed in the wall of the section I and having its lower or outlet end opening into the section I slightly above the rib Il or 40 the latter. A port 20 is so formed in the upper from said section as to substantially clear the upper section and extend exteriorly adjacent 'to the latter when'the mid section is raised.` Said 60 post has a lug 23 outwardly projecting from its upper end and it is preferred to form the upper section with a vertically elongated, open-bottomed housing 2l to receive said post and lug when the mid section is raised. A pair of parallel In these views, the reference character l deigpd arms 2l secured to the upper end portion lower ends of coiled springs I8 comprsed bement, or oor.

position of the mid section by the lug 23 to restrain the arm 29 from downward swinging.

In installingy the described jack on a vehicle, the upper section is clamped in any suitable manner upon the frame 3| of the vehicle, with the free end portion of the arm 29 engaging beneath an axle 32 of the vehicle. As illustrated a block 33 is secured within and projecting from the channel of the frame 3i and the section I'is clamped to said block by a yoke 34. The arm 29 is upwardly held against the axle by a saddle member 35 clamped on and depending from the axle, aiording the arm freedom to slide transversely of the axle and rock about the pivotal end of the arm. A leaf spring 36 transmits load from frame 3i to axle 32 as in common practice.

Preferably one of the described Jacks will be4 permanently associated with each end portion of each axle of a vehicle, such arrangement not being illustrated, however, since it is broadly old in this art.

In use of described jack, when compressed air or other pressure fluid is admitted through duct 3 to the section I, the' spring I8 normally raising the mid section of the jack is overcome and the mid section assumes its lowered position shown in Fig. 1. The post 22 is carried downwardly with the mid section assuming a position (Fig. 1) interengaging the lugs 23 and 30. 'I'his restrains the axle-supporting arm from downward swinging and assures that the axle 32 will not be materially lowered by sagging of the adjacent vehicle spring, when latter is relieved of load by the jack. Uncovering of the by-pass I9 upon lowering of the mid section admits the energizing iluid by port 20 to upper portion of said section, whereby the `spring li8 normally raising the bottom jack section is overcome and the latter descends to engage base I4 with the ground, pave- When air is permitted to vent from the upper section, the check valve 9 opens to effect venting of the mid section, and the springs I8 restore the two extended sections to their normal raised positions.

It will` be noted that the arm 29 is perfectly free to rock, when the jack is raised, so as to avoid interference with free relative vertical play of the frame and axle.

In the modification disclosed in Figs. 5` and 6, the parts i', 2', 3', 4', il', I4', Il', 2|' and 22' conform substantially to the corresponding parts above described, no housing being provided however, for the post 22', which carries at its upper end a iixed pin 23' projecting from opposite sides of the post. A lever member, comprising an approximately elliptical loop 40, is pivoted by pins 40a substantially on the shorter axis of such ellipse to the lower portion of the cylinder i which projects upwardly therethrough having ample clearance from the ends of said loop for pivotal movement of the lever. Preferably integrally formed at one end of the lever is an apertured guide member 4I through which freely projects said post 22', the pin 23' on such post resting when the jack is extended, in grooves 42 formed in the vupper face of the guide member 22' from lateral movement, prevents the cylinder 4' from rotating.

From the opposite end of the loop 4l in a plane substantially parallel with that of the loop extends an axle-supporting bar 43 which lifts and/or supports a vehicle axle 44 in raised position, when the jack is extended. Depending from a lug 49 projecting from the upper portion of the section I', is a spring 41 engaging said bar 43 to restrain the bar from downward swing The inner mechanism and operation of the cylinders i', 4', and Il' of the modincation correspond to that of the nrst described construction. As the cylinder 4' descends, the pin 23 on the upper end of thepost 22' engages the lever l4|", 40, 43 at 4l, holding such lever in axle-supporting position and thus preventing lowering of the axle due to sagging of a vehicles springs when the frame of such vehicle is raised by the jack.

The 'prevention of sagging of the springs and consequent lowering of the axle is highly desirable, since in absence of such prevention, a greater lift would be required of the jack, and this would 4 necessitate longer sections, and materially increase dimcuity or instauing the jack permal nently in limited space available. In some prior constructions, it has been proposed to swing a permanently installed jack normally to a horizontal position, but such complicationbecomes unnecessary when sagging of the springs is prevented;

such changes and modifications as come within the scope of the' following claims.

What we claim is:

1. A jack installed on a vehicle having anunsprung lower portion and a sprung upper portion, said jack comprising an upper hollow cylindrical section, means for attaching such section to the sprung portion of the vehicle, a section slidable within said upper section from a raised idle position to a lowered lifting position, a

spring reacting between said sections to normally maintain the raised position of the sliding section, means for delivering a pressure fluid to the upper section to react between the two seetions for lowering the sliding section, an arm pivotally mounted on the sprung portion of the vehicle and engageable at one side of its pivot be-- neath the unsprung portion of the vehicle to rie-v sist sagging of the unsprung portion, and means carried bythe sliding section engageable with said arm in a lowered position of the sliding section to maintain the arm in its eiiective position.

2. A jack as set forth in claim 1, said arm-engaging means consisting of a post 'secured to thelower portion of said sliding `section and upwardly projecting in an outwardly spaced relation to the sliding section, such as to clear the upper section. said post having a projection on its upper end for operatively engaging the pivotal arm.

3. In a jack as set forth in claim 1, a pivotal support for said arm carried by the lower portion of the upper section.

4. In a vehicle jack as set forth in claim 1, said arm-engaging means consisting of a post secured to the lower portion of the sliding section, and upwardly projecting in an outwardly spaced relation to the sliding section such as to clear the upper Section, said post having a projection on its upper end for operatively engaging the pivotal arm, and a housing exteriorly carried by the upper section and receiving said post in the raised position of the sliding section.

5. In a jack as set forth in claim 1, said armengaging means consisting of a post secured to the lower portion of the sliding section, and upwardly projecting in an outwardly spaced relation to the sliding section such as to clear the upper section, said post having a projection on its upper end for operatively engaging the pivotal arm, a housing exteriorly carried by the upper section and receiving said post in the raised position ofthe sliding section, a shaft pivoting said arm, and a pair of spaced supports for said shaft attached to said housing at opposite sides thereof and extending downwardly and outwardly from the housing to receive the shaft. l

6. A vehicle jack comprising an upper hollow cylindrical section, means for attaching such section to a sprung portion of a vehicle, a hollow cylindrical mid section slidable within the upper section from a raised idle position to a lowered lifting position, said section having a head at its upper end in fluid-sealed engagement with the upper section, a bottom section slidable in the mid section from a raised idle position to a lowered lifting position, springs effective on the sliding sections to normally maintain their raised positions, means for delivering a pressure fluid to the upper section to react between the upper section and said head for lowering themid secv tion, means effective in the lowered position of the mid section for establishing a fluid flow from the upper section to the interior of the mid section to effect subsequent lowering of the bottom section, and means including an actuating element connected to the mid section for resisting sagging of an unsprung portion of the vehicle when the mid section is lowered.

7. A vehicle jack as set forth in claim 6, said means for-establishing a fluid ow to the mid section consisting of a by-Dss carried by the upper sectionand having an inlet and an outlet vertically spaced to afford positioning of said head between the inlet and outlet in the lowered position of the mid section, and a port in the upper 'part of the mid section for admitting by-passed iluid to the interior of the mid section.

8. In a vehicle jack as set forth in claim 6, said lhead having a port for the escape of fluid from the mid section to the upper section, and a check valve controlling said port and opening responsive to a predeterminedreduction of fluid pressure in the upper section below that in the mid Section.

9. A vehicle Jack comprising an upper hollow cylindrical section carrying means for engaging a sprung portion of a vehicle, a section slidable within said upper section from a raised idle position to a lowered lifting position. a spring reacting between said sections to normally maintain the raised position of the sliding section, means for delivering a pressure fluid to the upper section to react between the two sections for lowering the sliding section, an arm pivoted to said upper section and engageable at one of its ends beneath an unsprung portion of a vehicle to -resist sagging of the unsprung portion, and means carried by the sliding section engageable with the opposite end of said arm in a lowered position of the sliding section to maintain the arm in its effective position.

10. A vehicle jack comprising an upper section carrying means for engaging a sprung portion of av vehicle, a lower section reacting against said upper section to downwardly extend such lower section and raise said sprung portion, an arm pivoted on the upper section to maintain an unsprung portion of the vehicle in raised position,

and a member iixed on the lower section to retain the arm 'in effective position, in a downwardly extended position of the lower section.

11. A vehicle jack as set forth in claim 10, said arm being pivoted at opposite sides of said upper section.

12. A vehicle jack as set forth in claim 10, said arm being pivoted' at opposite sides of said upper section, and having an apertured end freely slidably engaging said fixed member.

13. A vehicle jack as set forth in claim l0 having a spring reacting between said upper section and the arm to maintain the arm in contact with said unsprung portion of the vehicle.

14. A vehicle jack as set forth in claim 10, said arm projecting beyond the upper section in one direction to take effect on the unsprung portion of the vehicle, and projecting beyond the upper section in the opposite direction for, co-action with said fixed member.

15. A vehicle jack comprising an upper hollow cylindrical section, means for attaching such section to a Sprung portion of a vehicle, a hollow cylindrical mid-section slidable within the upper section from a raised idle position to a lowered lifting position, said sections having fluidsealing engagement, the upper section having a by-pass controlled by travel of `the mid-section and establishing a fluid delivery to the mid-section upon a predetermined downward actuation of the mid section, a bottom section slidable in and having fluid-sealing engagement with the midsection and actuable from a raised idle position to a lowered lifting position, and means for delivering a pressure fluid to the upper section to initially react between the upper section and mid-section for lowering the mid-section, and to subsequently react between the mid-section and bottom section for lowering the bottom. section.

16. A Vvehicle jack comprising telescoping upper and lower sections, means for securing said upper section to a sprungl portion of a vehicle. the lower section being slidable substantially vertically on the upper section from a raised idle position to a lowered lifting position, and means including an actuating element connected to the lower section for resisting sagging of an unsprung portion of the vehicle when vthe lowe section is in lifting position.

17. In a vehicle jack as set forth in claim 16, a spring resisting lowering of the lower section.

WALTER BEHM.

EARL J. MCCLEILAN, Jl. 

